Carrier-frequency telegraph system



Y 1,634, 060 Jam 2289 1927, J VOPEL I I CARRIER FREQUENCY TELEGRAPH SYSTEM Filed Jan. 5, 1926 Fig.3

R R i k? ug R 62 pupinize'd lines.

Patented June 28, 1927.-

UNITED STATES I 1,634,060 PATENT, OFFICE.

JOHANNES VOPEL; 0F BERLIN-NEIIKOLLN, GERMANY, ASSIGNOR TO C. LORENZ AK- TIENGESELLSCHAFT, 0F BEBLIN-TEMPELHQF, GERMANY.

CARRlER FREQ'UENcY TELEGRAPH SYSTEM.

Application filed January 5, 1926, Serial No. 79,298, andin Ger'manyJanuary 20, 1925.

signalsthereby undergo a retardation, thesedisturbances being specially remarkable with A sign transmitted by means of annudamped alternating'current requires a considerable time in order to build up. In consequence a'relay interposed will not be actuated at once at the beginning of the sign, but only after some time. It is the object of the present invention to Overcome this inconvenience, by interconnecting a res-- onant circuit tuned to the frequencyemployed and which produces an increase of the starting amplitude of the individual signs at the sending station and henceforth an increase of the steepness of the incoming wave at the receiving station.

The invention will be best understood bynection with a double-acting key. In Figure 3, 1 means an alternating current generator, 2 and 3 are coupling coils, dis a self-1nductance, 5' a capacity, 6 a keying device,'7.

a transformer and 8. and 9 represent the transmission line. If the circuit consisting of the self-inductances 3 and 4 and capacity 5 is tuned'to the frequency generated by the generator 1, it acts like a fly-wheel circuit into the transmission line. owever by value of the loading by the key the amplitude will soon decay to the value determined by the steady current supply.' A sign produced in this way at the transmitting station is shown by Figure 4. At the receiving stationthe sign will then look somewhat as indicated by Figure 5 and it may be seen that the steepness of the received wave'due to the increased 1 starting energy has been'increased. The am 'limit value the amplitude endeavors to atta in after a longer time, will in both cases be 'thesame depending only on the energy supplied by the alternating current source.

The invention may also be employed in connection with a double-acting key as represented by way of example by the diagram of connections in Figure 6. The alternating current source 1 is working over-the coupling'coils 2 and 3' upon two resonant circuits (4", 5*) and (4 5). -These two circuits are controlled by a double-acting key (-6, 6 which connects alternately the one or the'other circuit with the transformer 7 and thereby with the line 8 and 9. By keying these two circuits currents are transmitted into the line which are displaced by 180 with respect to each other and which'produce when being commutatedat the receiving station alternately a positive and a negative current operating a suitable receiving apparatus.

What I claim is:

. 1. In a carrier frequency transmission system, in combination an alternatingcurrent source, a repeating transformer having itsprimary connected with said current source, a pair of circuits resonant to the carrier fre quency and containing each one half of the secondary of said repeating transformer and a capacity, a double acting key in connection with the arrangement to connect alternately the .one or the other of said pair of resonant circuits with a transmission line.

2. In a carrier frequency transmission sysof said pair of resonant circuits with a transmission line.

' 1 3. In a carrier frequency transmission system, in combination an alternating current source, a repeating transformer having its primary connected with said current source a pair of circuits resonant to the carrier frequency and containing each one half of the secondary of said repeating transformer and a capacity, a second repeating transformer having. its primary by means of a double U0 tem, in combination an alternating current acting key alternately connected With one of said resonant circuits and having its secondary connected with a transmission line.

4:. Ina carrier frequency transmission system, in combination an alternating current source, a repeating transformer having its primary connected with said current source .a pair of circuits resonant to the carrier frequency and containing each one half of the secondary of said repeating transformer an inductance coil and a capacity, a second repeating transformer having its primary by means of a double-acting key alternately connected With one of said resonant circuits and having its secondary connected with a trans- 5 mission line. 7

In testimony whereof I have aflixedmy signature.

JOHANNES vo PEL. 

